Glen updates?
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StephenB
New member
Some follow-up on the RX8...
I came in because the car started to sputter and wasn't running well at all. I could smell fuel and thought I had a bad leak or something... Not the case. The car had a 3/4 of a tank of fuel. We did drop out and replace the tank today and found the source of the smell. I did run it out of gas on Friday and it acted the same as it did in the race which is why I thought I may have had the gas issue. I did have bad plugs which I have now replaced. I also replaced the fuel pumps just in case those were an issue. I am really hoping it runs better, I am heading up to NHMS to do some testing this week. If anyone has any ideas on the sputter issues (after 20min at race speed) let me know.
The other issue with what feels like wheel spin is still a bit of a mystery and my largest concern at this point. I see tons of $$ being spent to figure out what the issue is and I am hoping to figure it out before all that $$ is gone! I am hopefully dropping of the "racing" rear-end on Monday to be looked at. At this point I have no idea what could be wrong with the car. We put it on the lift today and double checked all the suspension and everything appears to be fine. We also did cross weights and they all came out good. I did not drop out the transmission since I didn't have time ao I have not checked the clutch. If the diff comes back without any known issues then I will try to look at that then. I would love it If a few of you wouldn't mind watching a lap or so of the attached video and give me a few ideas on what may be wrong.
[ame]http://www.youtube.com/watch?v=Sz4ooW4geQQ[/ame]
Just added a Youtube video of a few laps of me during qualifying. I was chasing down Dad
Please don't give me a hard time about driving! This was only my third time driving the car and only the third session the car was ever on track!
If you watch all the way to the end you will get to see Dan Hall having a little fun
Stephen
PS: I never did find any info on photos for the weekend but I did see a lot of photographers on track. And YES if anyone gets a photo of me shooting some flames I will probably buy it
I came in because the car started to sputter and wasn't running well at all. I could smell fuel and thought I had a bad leak or something... Not the case. The car had a 3/4 of a tank of fuel. We did drop out and replace the tank today and found the source of the smell. I did run it out of gas on Friday and it acted the same as it did in the race which is why I thought I may have had the gas issue. I did have bad plugs which I have now replaced. I also replaced the fuel pumps just in case those were an issue. I am really hoping it runs better, I am heading up to NHMS to do some testing this week. If anyone has any ideas on the sputter issues (after 20min at race speed) let me know.
The other issue with what feels like wheel spin is still a bit of a mystery and my largest concern at this point. I see tons of $$ being spent to figure out what the issue is and I am hoping to figure it out before all that $$ is gone! I am hopefully dropping of the "racing" rear-end on Monday to be looked at. At this point I have no idea what could be wrong with the car. We put it on the lift today and double checked all the suspension and everything appears to be fine. We also did cross weights and they all came out good. I did not drop out the transmission since I didn't have time ao I have not checked the clutch. If the diff comes back without any known issues then I will try to look at that then. I would love it If a few of you wouldn't mind watching a lap or so of the attached video and give me a few ideas on what may be wrong.
[ame]http://www.youtube.com/watch?v=Sz4ooW4geQQ[/ame]
Just added a Youtube video of a few laps of me during qualifying. I was chasing down Dad
Please don't give me a hard time about driving! This was only my third time driving the car and only the third session the car was ever on track!If you watch all the way to the end you will get to see Dan Hall having a little fun
Stephen
PS: I never did find any info on photos for the weekend but I did see a lot of photographers on track. And YES if anyone gets a photo of me shooting some flames I will probably buy it
robits325is
New member
It sounds like the clutch is slipping.
StephenB
New member
Agreed. BUT why would it only do that in right hand turns? It doesn't do it in a straight line or in left hand turns at all.
Gary L
New member
After watching your video, my guess is that you replaced one open (or broken) rear end with another open rear end, ergo the same result. If that was a slipping clutch, it would happen in LH turns as much as RH. For that matter, it would have happened while going straight... and in any case you sure as Hell would have smelled it after that much slippage, gas fumes or no.
lateapex911
Super Moderator
And thinking along those lines check rear dsmper rates in rebound. if one is excessive it could hang the corner up perhaps
Marcus Miller
New member
Stock on an RX-8 is a torsen...
StephenB
New member
Thanks guys! I will check droop tomorrow. I wonder if the shock is damaged? Do you think a bad shock could do that?
Stephen.
PS: rear diff is from a second gen rx7 turbo. Special order through mazdaspeed with a three month wait. I do have someone at a diff/transmission looking at it. Someone smarter than me that knows what they are lookimg at!
Stephen.
PS: rear diff is from a second gen rx7 turbo. Special order through mazdaspeed with a three month wait. I do have someone at a diff/transmission looking at it. Someone smarter than me that knows what they are lookimg at!
JeffYoung
New member
Yes, but unlikely. It would literally have to be keeping the wheel from rebounding to the ground and overpowering the spring. Doubtful I think.
But Jake's post got me thinking. Are you running out of suspension travel on that side? Is anything binding? If so, and you are going "infinite wheel rate" you could get spin like that and even with the Torsen (is is a Torsen?) it could act like you had one wheel in the air.
But Jake's post got me thinking. Are you running out of suspension travel on that side? Is anything binding? If so, and you are going "infinite wheel rate" you could get spin like that and even with the Torsen (is is a Torsen?) it could act like you had one wheel in the air.
Thanks guys! I will check droop tomorrow. I wonder if the shock is damaged? Do you think a bad shock could do that?
Stephen.
PS: rear diff is from a second gen rx7 turbo. Special order through mazdaspeed with a three month wait. I do have someone at a diff/transmission looking at it. Someone smarter than me that knows what they are lookimg at!
dj10
New member
Thanks guys! I will check droop tomorrow. I wonder if the shock is damaged? Do you think a bad shock could do that?
Stephen.
PS: rear diff is from a second gen rx7 turbo. Special order through mazdaspeed with a three month wait. I do have someone at a diff/transmission looking at it. Someone smarter than me that knows what they are lookimg at!
Stephen,
IMO you would have noticed very unusual handling characteristics if the rebound was bound up someway especially on entry and mid off. Jack the car up and put another jack under the rear wheel then jack it up and quickley release it to see how the rebound is set. Do this to each wheel you want to check the rebound on. As you jack the wheel up you can also see or feel how the compression is, of course check for leaks.
Best of luck.
seckerich
New member
If you special ordered that diff I would be really disappointed. Very possible if it is the T2 clutch type it is not assembled correctly. If it is a torsen you will be hateing life for years to come in that chassis, they suck for the RX8. Stock Clutch type with a few mods is much better than what you have. When you get it back drop me a line and I will walk you through checking a few things out. Do not waste money throwing parts at the car.
Was the fuel problem the transfer pump?
Was the fuel problem the transfer pump?
StephenB
New member
I am picking the Diff back up tomorrow. Nothing wrong with it, they said it was in perfect shape. I can't remember exactly what they called it but I think they said it was "gear driven" (I was on the phone with them while multitasking at work). I am now thinking it has to do with the "droop" that a few others mentioned. It is a huge difference between the two sides... almost three inches! Coilovers are NOT set to the same spot.
As far at the sputter... we replaced the pump that was on the right side of the tank because it was not working. (Steve, when you say transfer pump are you refering to this one, the one on the passenger side?) We did not change the primary pump on on the drivers side which is what we are going to do now. I didn't happen to have one or I would have done that at the test day. The fuel pressure was not consistant at all. (Installed a permanent gauge inline that is hooked up just before the fuel rail on fuel test port) The fuel pressure was actually dipping as low as 15-20 when it was sputtering AND the fuel pump was humming extremely loud with inconsistant tone. At the test day this past week we tried plugs, coils, alternater, battery, relays, fuses, and checked voltage/amps for various parts. Nothing worked and we packed up a bit early.
Stephen
Steve, I tried to send a PM but I am not sure it ever worked. feel free to e-mail me or PM me. sblethen "at" RSTPerformance.com
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NOT what you want in a race car, especially one with suspension problems... Any kind of gear/helical diff will go fully open unless both wheels are firmly on the ground. Obviously, yours are not (and won't be when, for example, you hit a good bump and/or run over a curb.) This will be an ongoing source of frustration for you.
If some kind of loaded clutch-type diff is available to you, I'd recommend selling that diff to a street car owner and buying one.
GA